# #7-1字母大小写转换
# s= input()
# l=len(s)
# b=[None]*l
# for i in range(l):
#     if s[i].islower():
#         b[i]=s[i].upper()
#     elif s[i].isupper():
#         b[i]=s[i].lower()
#     else:
#         b[i]=s[i]
# for i in b:
#     print(i ,end="")

# # 7-2无间隙输出
# s=input()
# k=[]
# for i in s:
#     if i==" ":
#         continue
#     else:
#         k.append(i)
# for i in k:
#     print(i,end='')

#7-3 快乐的数字【分支循环】
# import time
#
# def is_happy_number(num):
#     visited = set()
#     while num != 1 and num not in visited:
#         visited.add(num)
#         num = sum(int(digit)**2 for digit in str(num))
#     return num == 1
#
# start_time = time.perf_counter()
# number = int(input())
# result = is_happy_number(number)
# end_time = time.perf_counter()
#
# if result:
#     print("True")
# else:
#     print("False")
#
# if end_time - start_time > 0.9:
#     print("False")



#7-4 查找指定字符【分支循环】

# s=input()
# k=input()
# m=k.rfind(s)
# if m==-1:
#     print("Not Found")
# else:
#     print("index = {}".format(m))

# 7-5 数字查找求和【分支循环】

# s = input()
# k = input()
# def baseBe(s):
#     base = ""
#     num = ["1", "2", "3", "4", "5", "6", "7", "8", "9", "0"]
#     for i in s:
#         if i in num:
#             base += i
#     return base
# a=int(baseBe(s))
# b=int(baseBe(k))
# print(a+b)